Method for shrinking fabric



y 1957 c. N. CONE ETAL METHOD FOR SHRINKING FABRIC 2 Sheets-Sheet 1Filed May 25, 1955 IN V EN TOR5' CLARENCE N. CONE LEE A. HUGHES M May21, 1957 c. N. CONE ET AL METHOD FOR SHRINKING FABRIC Filed may 25, 19552 Sheets-Sheet 2 CLARENCE N. CON E L EE A. HUGHES BY g l U S te Patet CMETHOD FOR SG FABRIC Application May 25, 1955, Serial No. 511,043

2 Claims. (Cl. 26-185) This invention relates to fabric shrinkingapparatus and methods and more particularly to fabric shrinkingapparatus and methods whereby the shrunken fabric retains to a verylarge degree its initial ability to withstand wear.

Shrinking methods and apparatus are Widely used for treating fabricsbefore they are made up into garments or the like to minimize furthershrinkage of the fabric in the hands of the consumer. The presently mostgenerally used so-called preshrinking processes are harsh in theirtreatment of'the fabrics in that they involve various warpwisemechanical compressive methods and sometimes weftwise stretching methodsoften accompanied by elevated temperatures and pressures at criticalpoints suflicient to materially reduce the resilience andstrength of thefabric and impair the life of the fibers themselves. The overall effecthas been a fabric of reduced wearing properties. This invention isparticularly applicable to fabrics such as heavy denims of the order of11 oz. to the yard which are primarily used in garments in which heavy,rugged wear is of utmost importance. Previously such fabrics have beenconsidered diflicult to preshrink satisfactorily but may now be easilytreated to obtain desired properties.

In accordance with the present invention, there are provided apparatusand methods by means of which fabric can be shrunk prior to its use inapparel or the like with no damage to the fabric or its ability towithstand hard use. This shrinkage further is of a type which hasimproved cutting and garment making characteristics and minimizedsubsequent area changes of an undesirable nature. This desirable resulthas been achieved by subjecting the fabric to simulated natural relaxingforces which tend to bring it into equilibrium conditions. The clothafter weaving is passed through a series of operations includingwettings and subsequent dryings with material flexing but without at anytime placing the fabric under radical stress, particularly tension orcompression, either warpwise or Weftwise. It is also to be noted thatthis invention permits a high throughput of fabric, however, without theutilization of any special equipment both of which factors are essentialto a successful and competitive operation in this field.

A representative embodiment of the invention from which the above andother features thereof can be readily understood by those skilled in theart is described below 7 having reference to the accompanying drawingsin which:

Figure 1A is a diagrammatic view in side elevation of the first stagesof an apparatus for carrying out the in vention; and r Figure 1B is adiagrammatic view in side elevation of the concluding stages of theapparatus illustrated by Figure 1A. Referring now to the drawings,placing Figures 1A and 1B end to end, the complete apparatus is showncarrying out the process of the present invention. The

fabric F is illustrated in dot-dash lines entering the apf: we a 2paratus at the left hand end of Figure 1A and leaving at the right handend of the complementary Figure 1B. The fabric as produced on the loomsusually is cut into lengths of about 60 yards and delivered to thefinishing department where it is classified as to color or style,combined in lengths of about 1000 yards by sewing the goods end to end,sheared, brushed and inspected. These are conventional steps and, ofcourse, may be varied considerably without materially modifying thesubsequent steps comprising the invention.

The fabric F then passes downwardly into a wetting out box 10 containingknown desired wetting, softening, sewing and other treating agents.

.A suitable and effective wetting agent is desired at this pointinasmuch as it is an important factor in the process that. the fabric berapidly and effectively wet at intervals in order to relax the warp andfiller yarns and assist them in combination with other elements of theinvention in reaching equilibrium conditions. The first treatment mustbe effective in penetrating rapidly any prior additive remaining on thefabric from the weaving and prior operations. The use of wetting agentsin textile processing is well known and any of the known penetrants forthat purpose may be used. For example, Sulphonated compounds, sold underthe trade name Triton X have been found effective. Softening agents orlubricants such as sulphonated oils, Sulphonated tallows may be used.Sulphonated tallow, sold under the trade name Estol T Sulfonated hasbeen found effective. Sulphonated mineral oils such as those sold underthe trade name Twitchell oils are known wetting, softening agents forcotton textiles. V

The geometry of the wetting out box and the amount of the wetting andtreating agent contained therein are related to the speed of travel ofthe fabric to afford an exposure in the bath of about 0.6 second, thetemperature guide means Hand 12, preferably in the form of freelyrotating rollers. The latter guide means 12 can also serve as oneelement of squeezing means formed by the companion rollers 12 and 13having resilient surfaces and carried by a suitable supporting framework 14 having suitable adjusting means for regulating a compression onthe rollers 12 and 13. The rollers 12 and 13 are so disposed above thewetting out box 10 that the residual liquid returns to the box. Passingupwardly from the squeeze rolls the wetted fabric is carried by conveyermeans 15 which can take the form of a canvas duct belt conveyer, onepulley 16 of which can be mounted on the frame 14 and another pulley 17of which can comprise the first can of a first drying cylinder stackindicated generally by the numeral 18.

The stack 18 includes, in-addition to the can 17, a plurality ofsuccessively laterally offset cans 19, 20, 21, 22, 23, 24, 25 and 26,all supported for rotation about horizontal axes, and all driven inrotation in successively opposite directions as indicated by thedirection of arrows in each, through a suitable adjustable drive means(not shown). The fabric F is passed from can to can moving back andforth and upwardly to the top of the stack 18, with the speeds ofrotation being adjusted to impose minimum warpwise strain on the fabric.The travel. of the fabric over the first can 17 is slightly greater thanthe subsequent surface speed over the cans of the stacks due to thethickness of the canvas belt of the conveyer 15 which in effect givescan 17 a greater diameter than the subsequent cans. This small degree ofoverfeed from can .17 precludes tensioning of the fabric in the stack18.

From the top of the stack 18 the fabric F is passed without tensionthrough a succession of driven drying stacks passing downwardly andupwardly in sequence .through each to a final drying stack 27corresponding generally to the stack 18 and arranged to carry the fabricdownwardly with minimum strain imposed thereon to an out feed guide inthe form of a freely turning roller 28. Between successive drying'stacksthe fabric is main- .tained in a relaxed condition by appropriateadjustmentof the .drive means which are individually adjustable for theseveral stacks. The fabric at all points between stacks and when passingto subsequent equipment, it is :to .be noted, is in a .relatively loose,sagging condition and is supported by rollers .or endless belts.

The cans of the several stacks'are heated, in accordance with preferredpractice, by steam to a tempera- .ture in .the range of 160 to .180? F..Somewhat higher or lower temperatures may be .used withi-theunderstand- .ing (a) that the .heat must be sufficiently high at thispoint, as well as at later iheatingz onegato influence the tendency ofthe fabric to move toward .a shrunk equilibrium condition in combinationwith the other steps disclosed and (b) must be sufficiently .low toavoid adversely affecting the 'fibers of the fabric resulting in loss oflife, resiliency and wearresistant qualities.

The fabric initially charged at the wetting box may normally haveashrinkageof about 10% .warpwise for example. Coming off of the laststack warpwise :contraction Or shrinkage will have been reduced about50% and may be of the order of 5 or 6%. The fabric relatively free fromstress or tension in its travel to this lpointin a wet conditioninitially and after being flexed many times, begins to assume apreshrunk condition resulting from tendency of the warp and weft threadswithin the fabric to reach an equilibrium under these conditions.

Passing from the last stack of drying cylinders the fabric is in arelatively stiff boardlike condition and .passes-toa flexing and drivingframe assembly indicated generally by the numeral 29 withthe fabricpassing under and over relatively closely spaced and vertically offsetrollers 30, 31 and 32 to a pair of complementary feed rolls 33 and 34,the latter pair being driven from a variable speed transmission 35 toabelt coupling 36 .in order .to minimize tension in the fabric. Passingin an 8 configuration through the driven feed rolls 33 and 34, thefabric is passed over a pair of vertically spaced guide rolls '37 and 38to effect a vertical downrun adjacent water spray means 39 which cantake the form of a water spray nozzle 40 supported on a shelf 41.

Passing from the lowermost guide roll the water sprayed fabric passesupwardly and around the major partiof the circumference of a dryingcylinder 42 driven vfrom the variable speed transmission through beltmeans 43'. A second drying cylinder 44 is journalled for rota- .tionabout a horizontal axis below the cylinder 42 and is driven therefrom bybelt means 45, with a guide roller '46 engaging the fabric between thecylinders 42 and 44 to control the wrap of 'the'fabric thereabout.Emerging from the cylinder 44 the fabric path is controlled by tguiderollers 47, 48 and 4910 pass to'a supporting or -carrier roll assemblyindicated generally by the numeral '50. The temperature of the dryingrollers 42 and 44,

necessary to accommodate the contractions occasioned by the fabricshrinkage.

Passing from the carrier assembly 50 the fabric is passed over a batteryof scrimp bars 51, which again flex the fabric, from which it isconveyed to a conventional Palmer 52 for completion of the dryingoperation and to impose a final finish. The Palmer 52 includes a largerotatable heated drum 53 around the major portion of the circumferenceof which the fabric is passed. The heated drum 53 is engaged over amajor portion of its circumference by an endless belt 54, which betweenits points of engagement with the drum 53 is conveyed over a series ofguide rollers 55, 56, 57, 58, 59, 60 and 61, the latter being disposedat the point of introduction of the blanket 54 to the circumference ofthe drum to define the nip into which the fabricis conventionallyintroduced. The Palmer 52 is driven from a suitably controlled drivingsource (not shown) to achieve a desired throughput which, in accordancewith the present invention, is related to the speed of the-dryingcylinders 42 and 44, the feed rolls 33 and 34, the several stacks ofdrying cylinders, of which 18 and 27.,are representative, and thewetting out box and squeeze roll assembly 10, 12 and 13 so as to imposeno warp tension upon the fabric. The Palmer is heated to a temperatureof between about 280 and 300 F.

Passing from the scrimp bars 5 1'the fabric to -be introduced into thePalmer is passed over a-guide roll 62 which is so disposed relative tothe nip defined by the guide roller 61 and the drum 53 that the fabricis introduced to the Palmer at a point at which the belt .54 is in arelatively unflexed condition, i. e., the surface of the belt 54 whichengages the fabric at the nip has assumed a curvature no greater thanthat of the drum 53, which is relatively large. .In this fashion, thefabric passes into and through the Palmer without the application ofwarpwise bunching or compressing forces applied thereto. The finishedfabric is conveyed from the Palmer 52 to a suitable storage means(notshown) by guide rollers 63, 64 and 65.

Additional wetting zones may be provided as the fabric moves through theprocessing apparatus, if desired. Also additional related heating andflexing elements may be provided as. desired along the route of thefabric if it is noted that the chaarcteristics of a given fabric orgarment :product'from such fabric would bebetter servedzby suchmodification to the disclosed process. The presently disclosed processand equipment has been found to be effective with heavy denims suitablefor the best'work :garment wear, particularly those requiring fabricswith the greatest life, resilience, abrasive resistance such'as tosaddle wear.

The finalfabric ready to ship tothe consumer has been found to haveawarpwise shrinkage of the order of 1% :and a weftwiseshrinkage of about3% or less with no additional processing steps applied. The shrinkagetest used .is ;the:standard (A..S. T. M.) for the industry. In thetables below examples .of shrinkage ;and abrasive tests have been setforth as typicalbut not limiting. The abrasive test wasalso standardinthe industry (A. S. T.'M.) using a rotary platform double head abraser,of the type made by the Taber Instrument Company.

Shrinking Tests Heavy Denims Cloth from .Finished Loom, Cloth,perpercent cent Example I:

Warpwlse 10.2 86 Fillingwlse 6. 16 3. 83 Example II:

Warpwise 11.23 l. 96 Fillingwlse 6. 93 3. 53

- "It will be noted that the presentrinvention gives andfective andnotable preshrunk condition to the cloth. This is accomplished with arapid throughput, with an assembly of conventional equipment, andwithout harsh treatment of the fabric. The fabric is not overshrunkwarpwise as is often the case with conventional compression shrinkingmethods, resulting in subsequent stretching which is undesirable fromthe garment cutters standpoint. The filling or weftwise shrinkage ofabout 3% is not considered undesirable from the garment cuttersviewpoint because of the manner or direction in which the filling ispositioned in the garment.

These abrasive tests illustrate by way of typical examples the materialimprovement in wearing qualities of the products of the herein disclosedinvention.

We claim:

1. A process for rapidly and continuously imparting equilibriumconditions to a woven fabric consisting in treating the fabric with awetting and penetrating agent to soften and relax the fibres of saidfabric, subsequently continuously flexing said fabric in a substantiallyuntensioned condition while subjected to temperatures of not greaterthan about 180 F., subsequently continuously rewetting said fabric, andcontinuously flexing and heating said fabric in a substantiallyuntensioned condition at temperatures not greater than 180 F.

2. A process for continuously and rapidly producing a resilient wovenfabric with maximum strength and wear-resistant properties having thewarp and filler threads in substantially equilibrium condition, saidprocess being free from harsh temperatures and mechanical compressiveaction in the plane of the fabric and being performed entirely in acondition substantially free from mechanically imposed tensions on saidfabric, comprising continuously passing said fabric through a wettingzone whereby the threads of said fabric are softened and relaxed,subsequently continuously passing said fabric through a flexing zone ina substantially untensioned condition while subjecting said fabric totemperatures of about to F., rewetting said fabric and againcontinuously flexing said fabric in a substantially untensionedcondition at temperatures of about 160 to 180 F., and finally flexingand subjecting said fabric to a pressing action with heat whereby afabric of good finish and superior wearing and preshrunk qualities isproduced.

References Cited in the file of this patent UNITED STATES PATENTS2,327,712 Huey et a1 Aug. 24, 1943 2,338,983 Thackston et a1. Jan. 11,1944 2,584,753 Spooner Feb. 12, 1952

1. A PROCESS FOR RAPIDLY AND CONTINUOUSLY IMPARTING EQUILIBRIUMCONDITIONS TO A WOVEN FABRIC CONSISTING IN TREATING THE FABRIC WITH AWETTING AND PENETRATING AGENT TO SOFTEN AND RELAX THE FIBRES OF SAIDFABRIC, SUBSEQUENTLY CONTINUOUSLY FLEXING SAID FABRIC IN A SUBSTANTIALLYUNTENSIONED CONDITION WHILE SUBJECTED TO TEMPERATURES OF NOT GREATERTHAN ABOUT 180*F., SUBSEQUENTLY CONTINUOUSLY REWETTING SAID FABRIC, ANDCONTINUOUSLY FLEXING AND HEATING SAID FABRIC IN A SUBSTANTIALLYUNTENSIONED CONDITION AT TEMPERATURES NOT GREATER THAN 180*F.